Synonymy

Crepidula aculeata - Parodiz, 1939 [in part]: 695. Hoagland, 1977 [in part]: 364.

Bostrycapulus aculeatus - Olsson & Harbison, 1953: 280. Simone, 2002 [in part]: 18.

Crepidula cf. aculeata - Australia. Collin, 2003a: 541– 593.

Crepidula cf. aculeata - Sydney. Collin, 2003b: 618– 640.

Holotype: Australian Museum #C400000, shell and ethanol-preserved soft parts. Shell illustrated in Figure 11; length = 14.8 mm; width = 11.8 mm; height = 4.1 mm. Frozen tissue of this specimen: FMNH 282361.

Type locality: Edwards Reef, Sydney, Australia. 33∞51¢S, 151∞13¢E. Low intertidal zone on rocks.

Other material from type locality: FMNH 282302 (paratypes).

Diagnosis: B. pritzkeri can be distinguished from the other species in Bostrycapulus by its large, globose protoconch, and direct development from large eggs that produce embryos lacking the larval features present in other direct developing species of Bostrycapulus. Diagnostic DNA sequence differences distinguishing B. pritzkeri from all other Bostrycapulus species are in the following positions in the COI sequences submitted to GenBank (position 1 = position 1537 of the D. yakuba mitochondrial geneome, GenBank # X03240): 183 (c), 256 (c), 315 (c), 360 (c), 395 (c), 417 (g), 444 (g), 471 (g), 477 (c).

Distribution: south-eastern Australia. The Australian National Museum contains shells with this morphology from the coast of New South Wales and Queensland, but the species identity of the latter material needs to be verified with additional observations of live material and genetic data.

Description: shell morphology and anatomy of B. pritzkeri are the same as B. aculeatus except that the yellow or cream pigment makes a pattern of radial stripes or narrow triangles extending from the edge of the foot to the mantle edge. Direct development proceeds from large, ~545 Mm, eggs. Intracapsular embryos retain few larval characters. The velum is reduced to a simple ridge at the base of the tentacle (Fig. 6) and the food groove is absent. There is no operculum and the head vesicle is medium-sized and free of yolk. The embryonic shell has widely spaced rows of granular sculpture which are not visible on the protoconchs examined with SEM. The very large egg size results in the most globose and least coiled of any Bostrycapulus protoconch (Fig. 5A).

Etymology: the name pritzkeri is in honour of R. Pritzker, president of the Pritzker Foundation. The Foundation’s support of the Pritzker Laboratory of Molecular Systematics and Evolution at the Field Museum made this work possible.